fixup! iptunnel: add support to ipip, ipip6 and ip6ip6 tunnels

Author: liangwen12year

src/link/link_info/iptunnel.rs

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-use std::net::{IpAddr, Ipv6Addr};
+use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
 
 use anyhow::Context;
 use byteorder::{BigEndian, ByteOrder, NativeEndian};
@@ -50,7 +50,7 @@ pub enum InfoIpTunnel {
     Protocol(IpProtocol),
     PMtuDisc(bool),
     Ipv6RdPrefix(Ipv6Addr),
-    Ipv6RdRelayPrefix(Ipv6Addr),
+    Ipv6RdRelayPrefix(Ipv4Addr),
     Ipv6RdPrefixLen(u16),
     Ipv6RdRelayPrefixLen(u16),
     EncapType(TunnelEncapType),
@@ -66,7 +66,8 @@ impl Nla for InfoIpTunnel {
     fn value_len(&self) -> usize {
         use self::InfoIpTunnel::*;
         match self {
-            Ipv6RdPrefix(_) | Ipv6RdRelayPrefix(_) => 16,
+            Ipv6RdPrefix(_) => 16,
+            Ipv6RdRelayPrefix(_) => 4,
             Local(value) | Remote(value) => match value {
                 IpAddr::V4(_) => 4,
                 IpAddr::V6(_) => 16,
@@ -89,9 +90,8 @@ impl Nla for InfoIpTunnel {
     fn emit_value(&self, buffer: &mut [u8]) {
         use self::InfoIpTunnel::*;
         match self {
-            Ipv6RdPrefix(value) | Ipv6RdRelayPrefix(value) => {
-                buffer.copy_from_slice(&value.octets())
-            }
+            Ipv6RdPrefix(value) => buffer.copy_from_slice(&value.octets()),
+            Ipv6RdRelayPrefix(value) => buffer.copy_from_slice(&value.octets()),
             Link(value) | FwMark(value) | FlowInfo(value) => {
                 NativeEndian::write_u32(buffer, *value)
             }
@@ -231,14 +231,14 @@ impl<'a, T: AsRef<[u8]> + ?Sized>
                 }
             }
             IFLA_IPTUN_6RD_RELAY_PREFIX => {
-                if payload.len() == 16 {
-                    let mut data = [0u8; 16];
-                    data.copy_from_slice(&payload[0..16]);
-                    Self::Ipv6RdRelayPrefix(Ipv6Addr::from(data))
+                if payload.len() == 4 {
+                    let mut data = [0u8; 4];
+                    data.copy_from_slice(&payload[0..4]);
+                    Self::Ipv6RdRelayPrefix(Ipv4Addr::from(data))
                 } else {
                     return Err(DecodeError::from(format!(
                         "Invalid IFLA_IPTUN_6RD_RELAY_PREFIX, got unexpected \
-                         length of IPv6 address payload {payload:?}"
+                         length of IPv4 address payload {payload:?}"
                     )));
                 }
             }